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Transition metal single-atom catalysts with nitrogen-doped carbon substrates were designed and analyzed as the catalysts to oxidize Hg0 with O2, using density functional theory calculations, scaling relation analysis, and microkinetic modeling.

Background: Chronic kidney disease (CKD) eventually manifests as renal interstitial fibrosis, and loss of peritubular capillaries in the fibrotic area is the main marker of disease progression. Tie2, as the main functional receptor of angiopoietin, is characteristically expressed in vascular endothelial cells. This study aimed to evaluate the effect and mechanism of an agonistic Tie2 monoclonal antibody on folic acid (FA)-induced renal fibrosis (FAN) in mice.Methods: Mice were randomly divided into wild-type mice, FAN model mice, and FAN model mice treated with the agonistic Tie2 antibody. Human umbilical vein endothelial cells with lipopolysaccharide-induced injury were treated with the agonistic Tie2 antibody in vitro.Results: FA-induced renal tubulointerstitial lesions could be prevented with the agonistic Tie2 antibody. The extent of renal fibrosis induced by FA was suppressed by treatment with the agonistic Tie2 antibody. The level of fibroblast-specific protein 1 was reduced in mice that were administered the agonistic Tie2 antibody. Further, the agonistic Tie2 antibody inhibited FA‐induced vascular inflammation by downregulating vascular cell adhesion molecule-1. In addition, peritubular capillary density was upregulated by agonistic Tie2 antibody treatment, as evidenced by an increase in the level of cluster of differentiation 31. These findings were verified by the in vivo results, which showed that the levels of VCAM-1, Bax, and α-smooth muscle actin were downregulated after treatment with the agonistic Tie2 antibody.Conclusions: Based on all these findings, it appears that the agonistic Tie2 antibody attenuated renal interstitial fibrosis in FAN model mice by promoting peritubular capillary regeneration, inhibiting inflammation, and improving peritubular capillary lesions, and therefore, it may have promise for the treatment of CKD.

Based on various experimental results, M3+O(–Mn4+)2 clusters in (Fe, Co, Ni)-doped MnOx catalysts were identified as the principal active sites for the aerobic oxidation of 5-hydroxymethylfurfural due to their special properties that make oxygen ‘easy come, easy go’.

Pt nanoparticles supported on three-dimensionally ordered macroporous carbon (Pt/3DC) were prepared and applied as catalyst after chirally modified with cinchonidine for the enantioselective hydrogenation of ethyl pyruvate. The catalyst was characterized by SEM, TEM, powder XRD, N 2 sorption, and CO chemisorption, which confirmed the well-defined periodic macroporous structure of Pt/3DC and the high dispersion of Pt nanoparticles on the support. High catalytic performance was achieved over chirally modified Pt/3DC catalyst in the asymmetric hydrogenation of ethyl pyruvate. A high turnover frequency of 11,800 h −1 with an enantiomeric excess of 79.5% was acquired in acetic acid. In particular, this catalyst exhibited high durability in the asymmetric hydrogenation system and could be easily reused at least 13 times with well-maintained catalytic activity and slightly decreased enantioselectivity. Moreover, the comparison of catalytic performance between Pt/3DC and commercial Pt/C as well as Pt/Al 2 O 3 was carried out.

With the rapid development of detection technologies, compatible stealth in the infrared and radar ranges has become increasingly essential not only for military application but also for personal privacy protection. In this study, we design a metamaterial window that possesses stealth ability in both the thermal infrared and broadband microwave ranges, using a particle swarm optimization algorithm to realize multi-band optimization. We experimentally verify that the proposed structure can achieve over 90% microwave absorption in the range 5.1 to 19.2 GHz (covering the X and Ku bands), with low infrared emissivity (∼0.15), and also maintain visible transmittance above 60%. Moreover, the window retains good performance up to 200 °C owing to the intrinsic properties of the material. Our multi-band optimization method enables the application of the transparent metamaterial windows in electromagnetic shielding and stealth and can potentially be applied in smart window related industries.

The novel visible-light-driven 3DOM-SrTiO3/Ag/Ag3PO4 ternary composites were fabricated and used as photocatalysts in the degradation of organic contaminants, including RhB, phenol, and MB. Through the XRD, SEM, TEM, DR UV–vis, XPS, PL spectroscopy, N2 sorption, and photoelectrochemical measurement, the obtained 3DOM-SrTiO3/Ag/Ag3PO4 ternary composites were well characterized. The effects of SrTiO3:Ag3PO4 molar ratio and stop-bands of 3DOM-SrTiO3 on the catalytic performance were systemically investigated. 3DOM-SrTiO3/Ag/Ag3PO4 ternary composite photocatalysts exhibited notably enhanced activity compared with single 3DOM-SrTiO3 and Ag3PO4 catalyst. Among these ternary photocatalysts, S35A65(300) exhibited the most excellent photocatalytic performance under visible light irradiation, which could be mainly attributed to synergy effect of the notably improved separate efficiency of photogenerated electron-hole pairs and the suitable stop-bands of 3DOM-SrTiO3(300) material. Although the gradually reduced activity in cycling tests was obtained over S35A65(300) under visible light irradiation, an excellent durability could be achieved for S35A65(300) under UV–vis light irradiation. No obvious loss in photocatalytic efficiency was observed after six cycles for RhB degradation. The notably improved enhanced durability of 3DOM-SrTiO3/Ag/Ag3PO4 ternary composites under UV–vis light irradiation could be mainly attributed to the Z-scheme mechanism of this ternary composite photocatalyst.

Three-dimensionally ordered macroporous SrTiO 3 (3DOM-SrTiO 3 ) materials with different pore sizes were originally prepared and employed as photocatalysts in the water splitting for hydrogen generation. These 3DOM-SrTiO 3 photocatalysts were characterized by XRD, SEM, TEM, EDS, DR UV–vis and N 2 sorption. Because of the slow photon effect of 3DOM-SrTiO 3 , notably enhanced efficiency of water splitting for hydrogen evolution was obtained compared with the solid-state SrTiO 3 (SS-SrTiO 3 ) and disordered porous SrTiO 3 (Disorder-SrTiO 3 ). The effect of stop-band on the efficiency of photocatalytic hydrogen production was studied by tuning the pore diameter of 3DOM-SrTiO 3 . It was found that higher hydrogen evolution efficiency could be achieved when the photonic stop-band of 3DOM-SrTiO 3 was overlapped with its band gap, which was further confirmed by the control experiments under certain wavelength light irradiation. 3DOM-SrTiO 3 (270 nm) exhibited the highest photocatalytic hydrogen evolution rate (up to 3599 μmol/g·h), which was 31 times as high as that of SS-SrTiO 3 and 11 times higher than that of Disorder-SrTiO 3 . Furthermore, these 3DOM-SrTiO 3 catalysts were very stable and no obvious loss in photocatalytic efficiency of hydrogen production was observed after five cycles.

The three-dimensionally ordered macroporous alumina-carbon composite materials were firstly prepared through a surfactant-assisted colloidal crystal template method and applied to support Pt nanoparticles. The results of SEM, XRD, TEM and N2 sorption revealed that these composite materials possessed highly ordered macroporous structures with meso- and micropores within the skeletons of macropores and that the Pt nanoparticles were well dispersed on these materials with a very narrow size distribution. These prepared Pt nanocatalysts were evaluated in the asymmetric hydrogenation of ethyl pyruvate after chiral modification with cinchonidine. Excellent catalytic activity and enantioselectivity were achieved. More importantly, these catalysts exhibited extraordinary stability and reusability during the reaction and could be reused at least 26 times without obvious loss in catalytic activity and enantioselectivity.

Quantum dots (QDs) are promising materials used for room temperature mid-infrared (MIR) photodetector due to their solution processing, compatibility with silicon and tunability of band structure. Up to now, HgTe QDs is the most widely studied material for MIR detection. However, photodetectors assembled with HgTe QDs usually work under cryogenic cooling to improve photoelectric performance, greatly limiting their application at room temperature. Here, less-toxic SnTe QDs were controllably synthesized with high crystallinity and uniformity. Through proper ligand exchange and annealing treatment, the photoconductive device assembled with SnTe QDs demonstrated ultralow dark current and broadband photo-electric response from visible light to 2 μm at room temperature. In addition, the visible and near infrared photo-electric performance of the SnTe QDs device were well maintained even standing 15 d in air. This excellent performance was due to the effective protection of the ligand on surface of the QDs and the effective transport of photo-carriers between the SnTe interparticles. It would provide a new idea for environmentally friendly mid-IR photodetectors working at room temperature.

An environmentally benign and homogeneous base-free route for 5-hydroxymethyl-2-furfural (HMF) aerobic oxidation to 2,5-furandicarboxylic acid (FDCA) in water was reported using Mg–Al–CO3 hydrotalcite-supported Pd nanoparticles (xPd/HT-n) as catalyst. The influences of the Mg/Al molar ratio of hydrotalcite and Pd loading amount on the catalytic performance of these catalysts were originally systematically investigated. These catalysts exhibited excellent catalytic activity and FDCA selectivity in the HMF oxidation, especially for 2%Pd/HT-5 and 2%Pd/HT-6; >99.9% FDCA yields were achieved for 8 h under ambient pressure and homogeneous base-free conditions. The remarkably improved catalytic performance could be attributed to the suitable basicity of the Mg–Al–CO3 hydrotalcite and the abundant OH– groups on the surface of hydrotalcite. The plausible reaction mechanism was proposed based on the results of a series of controlled experiments. Furthermore, these catalysts were quite stable and could be reused at ...

We thank Prof. J.-Q. Yu for a useful discussion. This work was supported by Tianjin Municipal Natural Science Foundation (Grant 17JCYBJC22600), China Scholarship Council (Grants 201606200096 and 201606200087), and the Fundamental Research Funds for the Central Universities. Computational support was provided by the Beijing Computing Center (BCC). Investigation of Bi-doping effects on the catalytic performance of Pt/3DOM-Ce1−xBixO2−δ in the aerobic oxidation of 5-hydroxymethyl-2-furfural allows us to reveal the promoted catalytically active sites: the asymmetrical oxygen vacancies coordinated with one Bi and up to three Ce cations, such as Bi-□(-Ce)3, where □ represents an oxygen vacancy, which can easily gain oxygen atoms in favor of the CeO2 structure, and, when filled with oxygen, easily release oxygen anions in favor of six-coordination for Bi3+. The loss of electrons in the reduction of oxygen atoms at these sites would be replenished by electron transfer from Pt nanoparticles eventually promoting the oxidation potential of the Pt nanoparticles. The present work points out that the promoted catalytic properties in Bi-doped CeO2 are mainly due to the asymmetric structures of the oxygen vacancies, rather than simply to the number of oxygen vacancies. The newly proposed model of asymmetrical active sites and electron transfer mechanism may shed light on the physicochemical properties of other solid solution substrate-supported metal nanoparticle catalysts. Postprint

This work was supported by the National High Technology Research and Development Program of China (Grant No. 2012AA063008), the Tianjin Municipal Natural Science Foundation (Grant Nos. 17JCYBJC22600 and 15JCTPJC63500), China Scholarship Council (Grant 201606200096), and the Fundamental Research Funds for the Central Universities. New ternary composites based on three dimensionally ordered macroporous (3DOM) SrTiO3 (CdS/Au/3DOM-SrTiO3) were prepared and used as photocatalysts in visible light (λ > 420 nm) photocatalytic water splitting for hydrogen evolution. Through optimizing the pore size of 3DOM-SrTiO3 materials and the loading amounts of Au and CdS, CdS/Au/3DOM-SrTiO3(300), templated by 300 nm sized poly(methyl methacrylate) colloids, was found to exhibit a remarkably enhanced photocatalytic hydrogen evolution rate (2.74 mmol/h•g), which was 3.2 times as high as that of CdS/Au/C-SrTiO3 catalyst based on commercial SrTiO3. This notably enhanced photocatalytic performance was mainly attributed to the slow photon enhancement effect of 3DOM-SrTiO3(300) material, which significantly promoted the light harvesting efficiency of ternary composite for the slow photon region of 3DOM-SrTiO3(300) was well matched with the optical absorption band of photocatalyst. Further depositing Pt nanoparticles on CdS/Au/3DOM-SrTiO3(300) composite as a co-catalyst, an extraordinarily high hydrogen evolution rate (up to 5.46 mmol/g•h) and apparent quantum efficiency (42.2% at 420 nm) were achieved because of the synergistic effect of efficient carrier separation, Au SPR effect, and slow photon effect. Furthermore, these ternary CdS/Au/3DOM-SrTiO3 composite photocatalysts were very stable and could be easily recycled four times in visible light photocatalytic water splitting experiments without any loss in activity. Postprint

Emotional agents are useful to variety of com- puter applications. This paper focuses on the emotion of surprise. Surprise can be considered as the automatic reaction to a mismatch, which plays an important role in the behaviors of intelligent agents. We represent psychological theories of surprise through fuzzy inference systems, as fuzzy logic helps to capture the fuzzy and complex nature of emotions. We infer the degree of surprise from four factors relating to it by three kinds of fuzzy inference systems respectively, and propose fuzzy inference rules as well as reasoning parameters for the systems. Case study shows the surprise generation process by fuzzy inference system. The surprise inference system can be applied into the decision making process of agents in uncertain environments.

Emotions convey information. We present an emotion understanding system to excavate information from emotions. The system infers mental states, personalities and cooperativeness of agents, related actions, and related events from agents' emotions by the rule-like meta-knowledge about emotions. Our system can be used for agents to make decisions, process knowledge, and interact with users.

Pure perovskite 0.68Pb [Mg 1/3 (Nb (1-x) Ta x ) 2/3 ]O 3 -0.32PbTi03 (0.68PMNTa-0.32PT) ceramics were prepared by one-step calcination method using Mg(NO 3 ) 2 instead of MgO as starting chemical. The dielectric properties as a function of temperature and P-E and -E loops were investigated in this work. The T m and T c shift down for ∼13 °C with Ta addition. The e m with Ta-doping is higher than that without doping. Both of the diffusion phase transition and frequency dispersion are weak, but the relaxor feature with Ta-doping is more apparent than that without doping. Both of the values of P r and E c decrease with Ta addition, and the values of remnant and maximum strain increase with Ta-doping.

Insulin resistance results in dysregulated hepatic gluconeogenesis that contributes to obesity-related hyperglycemia and progression of type 2 diabetes mellitus (T2DM). Recent studies show that MAPK phosphatase-3 (MKP-3) promotes gluconeogenic gene transcription in hepatoma cells, but little is known about the physiological role of MKP-3 in vivo. Here, we have shown that expression of MKP-3 is markedly increased in the liver of diet-induced obese mice. Consistent with this, adenovirus-mediated MKP-3 overexpression in lean mice promoted gluconeogenesis and increased fasting blood glucose levels. Conversely, shRNA knockdown of MKP-3 in both lean and obese mice resulted in decreased fasting blood glucose levels. In vitro experiments identified forkhead box O1 (FOXO1) as a substrate for MKP-3. MKP-3-mediated dephosphorylation of FOXO1 at Ser256 promoted its nuclear translocation and subsequent recruitment to the promoters of key gluconeogenic genes. In addition, we showed that PPARγ coactivator-1α (PGC-1α) acted downstream of FOXO1 to mediate MKP-3-induced gluconeogenesis. These data indicate that MKP-3 is an important regulator of hepatic gluconeogenesis in vivo and suggest that inhibition of MKP-3 activity may provide new therapies for T2DM.

SIRT4, a member of the sirtuin family, has been implicated in the regulation of insulin secretion by modulation of glutamate dehydrogenase. However, the role of this enzyme in the regulation of metabolism in other tissues is unknown. In this study we investigated whether depletion of SIRT4 would enhance liver and muscle metabolic functions. To do this SIRT4 was knocked down using an adenoviral shRNA in mouse primary hepatocytes and myotubes. We observed a significant increase in gene expression of mitochondrial and fatty acid metabolism enzymes in hepatocytes with reduced SIRT4 levels. SIRT4 knockdown also increased SIRT1 mRNA and protein levels both in vitro and in vivo. In agreement with the increased fatty acid oxidation (FAO) gene expression, we showed a significant increase in FAO in SIRT4 knockdown primary hepatocytes compared with control, and this effect was dependent on SIRT1. In primary myotubes, knockdown of SIRT4 resulted in increased FAO, cellular respiration, and pAMPK levels. When SIRT4 was knocked down in vivo by tail vein injection of a shRNA adenovirus, we observed a significant increase in hepatic mitochondrial and FAO gene expression consistent with the findings in primary hepatocytes. Taken together these findings demonstrate that SIRT4 inhibition increases fat oxidative capacity in liver and mitochondrial function in muscle, which might provide therapeutic benefits for diseases associated with ectopic lipid storage such as type 2 diabetes.

PGC-1alpha (peroxisome proliferator-activated receptor gamma coactivator 1alpha) is a master regulator of mitochondrial biogenesis and plays an important role in several other aspects of energy metabolism. To identify upstream regulators of PGC-1alpha gene transcription, 10,000 human full-length cDNAs were screened for induction of the PGC-1alpha promoter. A number of activators of PGC-1alpha transcription were found; the most potent activator was the transducer of regulated CREB (cAMP response element-binding protein) binding protein (TORC) 1, a coactivator of CREB. The other two members of the TORC family, TORC2 and TORC3, also strongly activated PGC-1alpha transcription. TORCs dramatically induced PGC-1alpha gene transcription through CREB. Forced expression of TORCs in primary muscle cells induced the endogenous mRNA of PGC-1alpha and its downstream target genes in the mitochondrial respiratory chain and TCA cycle. Importantly, these changes in gene expression resulted in increased mitochondrial oxidative capacity measured by cellular respiration and fatty acid oxidation. Finally, we demonstrated that the action of TORCs in promoting mitochondrial gene expression and function requires PGC-1alpha. Previous studies had indicated that TORCs function as a calcium- and cAMP-sensitive coincidence detector and mediate individual and synergistic effects of these two pathways. Our results, together with previous findings, strongly suggest that TORCs play a key role in linking these external signals to the transcriptional program of adaptive mitochondrial biogenesis by activating PGC-1alpha gene transcription.

Abstract— Biomechanical strain is a stimulus for cardiomyocyte hypertrophy and heart failure, but the underlying molecular mechanisms remain incompletely understood. Using an in vivo murine model of pressure overload and an in vitro model of mechanical stimulation of primary cardiomyocytes, we identified iex-1 as a gene activated during the early response of cardiomyocytes to hypertrophic stimuli and as a gene product that inhibits hypertrophy without affecting cardiomyocyte viability. On stimulation of cardiomyocytes, iex-1 mRNA and protein expression increased and translocation of the gene product to the cardiomyocyte nucleus occurred. iex-1 has previously been proposed as a mediator of NF-κB-dependent cell survival and growth in tumor cells. Here, we demonstrate that the biomechanical induction of iex-1 in cardiomyocytes was NF-κB-dependent, as overexpression of the NF-κB inhibitor IκBα completely inhibited strain-mediated iex-1 mRNA accumulation. The functional role of iex-1 was investigated by overexpressing wild-type iex-1 with replication-defective adenoviral gene transfer. Overexpression of iex-1 abolished cardiomyocyte hypertrophy by mechanical strain, phenylephrine, or endothelin-1 at levels that did not affect cell viability. These studies identify iex-1 as a biomechanical stress-inducible and NF-κB-dependent gene in cardiac muscle cells during the acute phase of hypertrophy with negative growth regulatory effects that may counterbalance early hypertrophic responses in activated cardiomyocytes.

In the mechanically active environment of the artery, cells sense mechanical stimuli and regulate extracellular matrix structure. In this study, we explored the changes in synthesis of proteoglycans by vascular smooth muscle cells in response to precisely controlled mechanical strains. Strain increased mRNA for versican (3.2-fold), biglycan (2.0-fold), and perlecan (2.0-fold), whereas decorin mRNA levels decreased to a third of control levels. Strain also increased versican, biglycan, and perlecan core proteins, with a concomitant decrease in decorin core protein. Deformation did not alter the hydrodynamic size of proteoglycans as evidenced by molecular sieve chromatography but increased sulfate incorporation in both chondroitin/dermatan sulfate proteoglycans and heparan sulfate proteoglycans (p0.05 for both). Using DNA microarrays, we also identified the gene for the hyaluronan-linking protein TSG6 as mechanically induced in smooth muscle cells. Northern analysis confirmed a 4.0-fold increase in steady state mRNA for TSG6 following deformation. Size exclusion chromatography under associative conditions showed that versican-hyaluronan aggregation was enhanced following deformation. These data demonstrate that mechanical deformation increases specific vascular smooth muscle cell proteoglycan synthesis and aggregation, indicating a highly coordinated extracellular matrix response to biomechanical stimulation.

Background —Unstable atherosclerotic lesions typically have an abundant inflammatory cell infiltrate, including activated T cells, macrophages, and mast cells, which may decrease plaque stability. The pathophysiology of inflammatory cell recruitment and activation in the human atheroma is incompletely described. Methods and Results —We hypothesized that differential gene expression with DNA microarray technology would identify new genes that may participate in vascular inflammation. RNA isolated from cultured human aortic smooth muscle cells treated with tumor necrosis factor-α (TNF-α) was examined with a DNA microarray with 8600 genes. This experiment and subsequent Northern analyses demonstrated marked increases in steady-state eotaxin mRNA (>20 fold), a chemokine initially described as a chemotactic factor for eosinophils. Because eosinophils are rarely present in human atherosclerosis, we then studied tissue samples from 7 normal and 14 atherosclerotic arteries. Immunohistochemical analysis demonstrated overexpression of eotaxin protein and its receptor, CCR3, in the human atheroma, with negligible expression in normal vessels. Eotaxin was predominantly located in smooth muscle cells. The CCR3 receptor was localized primarily to macrophage-rich regions as defined by immunopositivity for CD 68; a minority of mast cells also demonstrated immunopositivity for the CCR3 receptor. Conclusions —Eotaxin and its receptor, CCR3, are overexpressed in human atherosclerosis, suggesting that eotaxin participates in vascular inflammation. These data demonstrate how genomic differential expression technology can identify novel genes that may participate in the stability of atherosclerotic lesions.

Abstract —Vascular smooth muscle cells must monitor and respond to their mechanical environment; however, the molecular response of these cells to mechanical stimuli remains incompletely defined. By applying a highly uniform biaxial cyclic strain to cultured cells, we used DNA microarray technology to describe the transcriptional profile of mechanically induced genes in human aortic smooth muscle cells. We first identified vascular endothelial growth factor (VEGF) as a mechanically induced gene in these cells; VEGF served as a positive control for these experiments. We then used a DNA microarray with 5000 genes with putative functions to identify additional mechanically induced genes. Surprisingly, relatively few genes are mechanically induced in human aortic smooth muscle cells. Only 3 transcripts of 5000 were induced >2.5-fold: cyclooxygenase-1, tenascin-C, and plasminogen activator inhibitor-1. Downregulated transcripts included matrix metalloproteinase-1 and thrombomodulin. The transcriptional profile of mechanically induced genes in human aortic smooth muscle cells suggests a response of defense against excessive deformation. These data also demonstrate that in addition to identifying large clusters of genes that respond to a given stimulus, DNA microarray technology may be used to identify a small subset of genes that comprise a highly specific molecular response.

Controlling the specific differentiation of stem cells (SCs) is a goal sought by many because of the benefits it would yield for repair or replacement of damaged tissues and organs. We report the discovery of signaling complexes and describe their use in predictably guiding the differentiation of mouse and human SCs. The signaling complexes (Signal-plexes™ [S-ps]) induce mouse and human SCs to express specific phenotypes. The S-ps have been used to identify a new source of human SCs (Hu abba-1™) and have been shown to induce differentiation of multiple tissue-specific phenotypes selectively in mouse pluripotent embryonic cells as well as in Hu abba-1 cells. Endocrine and exocrine pancreas, liver, lung, kidney, heart, cartilage, bone, and other cell types have been induced in SCs by S-ps, as shown by morphology, immunostaining, enzyme-linked immunosorbent assay, and reverse transcriptase–polymerase chain reaction analysis.